Private Sub CommandButton1_Click()
Worksheets("Feuil1").Range("A1").Value = "PO" & Format(Date, "yyyy-mm-")
If Worksheets("Feuil1").Range("A1").Value = "PO" & Format(Date, "yyyy-mm-") Then
[C1] = [C1] + 1
Worksheets("Feuil1").Range("D1").Value = 100 + Range("C1").Value
Worksheets("Feuil1").Range("B1").Value = Range("A1").Value & Range("D1").Value
End If
End Sub